Leather-cutting die and method of making shapes



H. C. STOCKMAN.

LEATHER CUTTING me AND METHOD 0T MAKING sHAPEs.

APPLICATION FILED MAR. 2l. |918.

Patented July 8, 1919.

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UNITED STATES PATENT OFFICE,

HENRY C. STOCKlVIAN, OF NEW YORK, N. Y., ASSIGNOR OF ONE-HALF TO HENRY STOCKMAN, OF ENGLEWOD, NEW JERSEY.

LEATHER-GUTTING DIE AND METHOD OF MAKING SHAPES.

Specification of Letters Patent.

Patented July 8, 1919.

Application filed March 21, 1918. Serial N o. 223,681.

To all whom t may concern.'

Be it known that I, HENRY C. S'rocKMAN, a citizen of the United States, and residing at New York, county of New York, `and State of New York, have invented new and useful Improvements in Leather-Cutting Dies and Methods of Making Shapes, of which the following is a specication.

This invention relates to the manufacture of shapes from flexible or semi-rigid material and is particularly adapted for the manufacture of half soles, heel-lifts and the like from leather. It has for its objects the expeditious and economical production of such articles without necessitating the rehandling of the same.

I am aware that it has heretofore been proposed in Jdie manufacture of said shapes to employ a cutting die of the desired shape having vertical inner and outer walls, the inner walls being perpendicular to the cutting edge of an upper cutting face. In practice such a die is placed in the desired position upon the grain or hair side of the leather and ,the same yare transferred to a press which forces the die through the leather, thereby forming blanks corresponding to the inside configuration of the die. Obviously, in such cases the blanks would remain wedged fastl in the die and the removal thereof was required in order to prepare .the die for the next cut. For this purpose it is necessary' not only to employ a skilled operator in'order to properly position the dieso as not to waste leather but also in order to obtain a satisfactory out-V put from such die owing to the necessary slowness of the operation.

My invention isfully described in detail in the accompanying specification and .drawings forming a part thereof, in which* Figure 1` is a diagrammatic plan view showing the shape of the cutting edge of the die used for making leather soles and showing also the cutting edge of a transverse parting knife;

Fig. 2 is a similar view of adie of modied configuration suitable for making leather heel-lifts.

Fig. 3 is a'vertical transverse section of a die of the configurationshown in Fig. 1, with its accompanying knock-out plate and with a ram or drop-hammer shown in elevation in a raised position with respect to the material to be punched, and

Fig. 4 is alongitudinal, vertical section of the apparatus shown in Fig. 3, but with the ram shown in its lowermost position, several blanks collected within the die chamber being also illustrated.

Referring to the drawings and the construction shown therein, the reference numeral 1 designates the bed plate of the press, which is provided with a chamber 2 conforming substantially to the enlarged lower chamber 3 of a die Ll. Said die is fixed so that said lower chamber is superposed on and registers with said chamber 2, being held by a suitable meta-l ring 5 bolted to said bed. As shown, said die, which is pref erably steel, is provided with an upper cutting edge 6, preferably highly tempered, and an upper beveled face 7 which extends from said cutting edge tov the outer wall 8. The upper inner wall 9 of said die, as shown, is vertical to said cutting edge 6 and forms an upper chamber lO'w-hich accurately approximates the said cutting edge `6 in configuration and cross sectional area. Centrally within said die is secured a transverse web or parting' knife 11 having an upper central cutting edge 12 and two oblique or beveled upper faces 13, 13 which extend to the sides 14, 1li of said knife. Said knife may be secured within said `die in any desired manner. The edge l2 of said parting knife preferably projects substantially above the top of the aforesaid enlarged chamber 8 and preferably extends through an intermediate chamber 15, of variablecross sectional area, to the bottom of the aforesaid chamber 10 for the reasons hereinafter ei;- plained. Said chamber 15 is a chamber formed by the oblique wall 16- which integrallyconnects the said lower walls il and said upper wall 9.of said die.

A knock-out member 17 is slidably mounted upon posts 18, 18', rigidly anchored in the ring 5, which project through ears or lugs 19, 19 on said member. Integral heads 2O on said posts serve as stops to limit the upward movement of the member 17, since the apertures of said lugs, as shown, are of smaller diameter than said heads and adapted only to receive the posts. The upper face of said knock-out member forms a table and the inner wall conforms to the outer wall of said die, but the beveled face a of said knock-out member is so arranged, according to the thickness ofthe material to be operated upon, that, when at its lowermost position during the operation of the press, it will lie in substantial parallelism, and out of contact, with the outer beveled face b of said die. Coil springs 21 which surround the posts 18 and bear at each of their ends against the ring 5 and the lugs 19, respectively, serve to normally hold the said knock-out member in an elevated position.

The ram or drop-hammer member 22, operated in the well known manner, is adapted to be forced downwardly into contact with a strip of material, for example, leather, which is placed upon the table formed by the upper face of said knock-out member. Said ram is adapted to force said knock-out member downwardly until the die completely severs a blank of the desired shape from the strip of material operated upon, and the extent of upward movement of said knock-out member regulated according to the thickness of the material operated upon.

The operation of the aforesaid parts, as is evident from the foregoing, consists in -repeatedly subjecting a strip of material to the action of said ram 22 until a sufficient number of blanks have collected in the upper chamber 10 to completely fill the same. Then as the next successive blank is formed by the operation of said press, the lowermost blank in said upper chamber, will be forced into contact with the cutting edge of the parting knife and wil-l bc completely severed by said parting knife simultaneously with the severing of the aforesaid blank from the strip of material operated upon. The beveled or inclined faces 13, 13 of said parting knife serve, as the lowermost blank is severed, to project the severed parts outwardly away from said knife and the same will then fall into the lower chamber 3, thence down into the chamber 2 of the bed of said press from which they may be gathered as desired without necessita-ting the interruption of the operation of the press.

Owing to the close fit of the blanks within the die against the inner walls thereof, the blanks will not of themselves drop through the die but will be held in position by the friction between the same and the said walls until positively forced downwardly by the entrance of a freshly formed blank into the die. Finally, as the upper chamber becomes filled with accumulated blanks the first blank formed will be severed as above described by the parting knife simultaneously with the formation of a new blank.

The parting knife constitutes as it were a wedge which serves to force the separated parts of the blank in opposite directions within the intermediate chamber in said die, which, as herein stated, is of increasing cross sectional area commencing with the upper end thereof and extending to the upper end of the lower compartment. As

`a consequence of the foregoing the Vblank will be accurately held in the proper position to be severed into two symmetrical parts but will be immediately released as soon as cut and the said parts may be collected in convenient receptacles placed beneath the press.

Having thus described my invention, what 1 claim and desire Ito secure by Letters Patent is 1. The method of making shapes which consists in causing a'die to successively sever a plurality of duplicate blanks of predetermined shape from a strip of material, `repeatedly confining each blank, immediately after forming the same, in a chamber within said die which snugly conforms to the configuration of said blank while subjecting a superposed strip of material to a successive forming operation of said die until a plurality of blanks are collected Awithin said chamber, and then substantial-ly simultaneously subdividing the lowermost blank into a plurality of parts while forcing a newly formed blank into said chamber and while substantially simultaneously releasing each of said subdivisions so formed 4into a space of substantially greater cross sectional area than itself.

2. The method of making shapes which consists in causing a die to successively sever a plurality of duplicate blanks of predetermined shape from a strip of semi-rigid, nonmetallic material, repeatedly confining each blank, immediately after forming the same, in a chamber within said die which snugly conforms to the configuration of said blank while subjecting a superposed strip of the said material to a successive forming operation of said die until a plurality of blanks are collected within said chamber, and then substantially simultaneously subdi-viding the lowermost blank into a plurality of parts while forcing a newly formed blank into said chamber and while substantially simultaneously releasing each of said subdivisions so formed into a space of substantially greater cross sectional area than itself.

3. The method of making shapes which consists in causing a die to successively sever a plurality of duplicate blanks of predetermined shape from a strip of leather, repeatedly confining each blank, immediatel after forming the same, in a chamber within said die which snugly conforms to the configuration of said blanks while subjecting a superposed strip of the said material to a successive forming operation of said die until a plurality of blanks are collected within said chamber, and then substantially simultaneously subdividing` the lowermost blank into a plurality of parts while forcing a newly formed blank into said chamber and while substantially simultaneously releasing each of said subdivisions so formed into a space of substantially greater cross sectional area than itself.

4. The method of making shapes from a strip of semi-rigid material which consists in successively forming a plurality of blanks one upon another, temporarily conining the blanks so formed in a chamber and causing the pressure exerted to form the uppermost blank to simultaneously effect the severing transversely of the lowermost blank by a cutting medium into a plurality of parts, and causing the separation of said parts from the superposed blanks.

5. An apparatus for cutting shapes from a strip of material comprising a hollow die having a relatively large chamber therein, a continuous cutting edge forming the upper edge of said chamber, an inner chamber having a substantial portion thereof of a uniform conguration substantially conforming to that of the said cutting edge, and another portion of said chamber being of greater area than said first portion, a tablet adapted to receive a strip of material to be operated upon, elastic means for normally maintaining the plane of said tablet above the upper level of said cutting edge, while permitting of the movement of said tablet, so that its plane lies below said cutting edge, a supplemental transversely disposed cutter projecting into said chamber, the upper edge of said second cutter projecting slightly above the enlarged portion of said chamber and means for depressing said tablet suiciently to cause the edge of the die to sever a blank from a strip of leather forced into engagement with said tablet and to simultaneously effect the severing of a similar blank confined within said die into a plurality of parts.

6. An apparatus, comprising an elastically supported tablet adapted to receive a strip of material, a hollow cuttino` die having a continuous cutting edge a apted to normally lie out of contact with a strip of material placed on said tablet, said die having a chamber therein closely conforming in cross sectional area and Vconfiguration to the said cutting edge and being adapted to contain a plurality of blanks formed by said die, and cutting means extending transversely respecting the lower part of said chamber operable by the pressure eXterted upon said strip of material when formin a blank, adapted to separate into a plurality of parts, the innermost blank of a series conlined in said chamber.

7. In an apparatus for making leather shapes, the combination comprising a hollow die adapted to deliver blanks cut by said die inwardly therethrough, means for forcing a strip of material to be operated upon into contract with the cutting edge of said die, and a supplemental severing medium eX- tending transversely respecting said die adapted to sever a blank passing through said die simultaneously with the formation of a fresh blank by said die,

Signed at New York, in the county of New York and State of New York, this 14th day of March, 1918.

HENRY C. STOCKMAN.

Copies of this patent may be obtained forve cents each, by addressing the Commissioner of Patents, Washington, D. 

